Electric generator



NOV. 23, 5 G DA E ET AL ELECTRI C GENERATOR Filed July 22, 1935 INVENTR5 ATTORNbY.

PM Nov. 23, 1 31 PATENT OFFICE ammnmsscuxenin hSwek-Jdyflll i4 chi-l.(a. 11m) Ourinvticnrelates to electric gensatusandmorepartlcularlytoelcctricgmentm'adeianed especially foruse incamectlon with bicycles. motmwcksor other vebicla.

iiculty has been expeiiencedincomtrneflr a generator which will developsuflldent volhge forthelm 'pmesdesimsuchassupplyingwrm rent for lightingand operatingwarningfllsnfls-Thevoltagedevelopedbyageneratorisihpuidentuponthereiativespeerkorltherotatimpuhanduponthe sineottheseparts. Anincrease of the vehicle I], such as thefork of a bicycle. Ball baring: II are. provided between members I! andI! and serve to rotatably mount the hub I. m the stationary shafts l6.

l'hed within mber III is a spider or disc 20 5 to which is secured aplurality of armature windlngs 2|. A bearing member 22 is secured to thecenter plate 2| and is provided at its inner end with a conical recess23.

A ring member 24 is secured within member II and B prderably formed witha groove 25 hav- 1! a rectangular cross-section. A plurality of wheelsor rollers 2' are mounted on shafts 21 fixed to a stationary plate orspider 28. Plate 28 is rlidly secured to the inner end of stub shaft l5l6. Rollers 2O frictionally engage the groove 25 d manhu- 24 and thecontact surfaces of these rollers are preferably circular so that theyenage member 24 only at the edges of groove 25. Roller 26also-frictionally engage a shaft 20, and nerve also as roller bearingsfor supporting (me end of the shaft. The other end of shaft 8. is formedwith a conical point which is recdved in conical recess 23, therebyserving to rotatahly support this end of the shaft. Axial mt of shaft 3.is prevented by a thrust block II carried by plate 28. The field o! thegenerator is mounted on shaft 30, and in the embodiment M, constitutespermanent magnet: 32. so

Armature coils 2| are connected in series and are d the electrical leads33 is grounded to acne metallic part of the hub while the other had 34passes through an opening 85 formed by hen-rim member 22 and isconnected to a contact in I carried by member 22. A brush 31 is slidablymounted in an insulating sleeve 39 secured within a bore a formed instubshaft I6 at the left-hand end of the 'hub, as viewed in Fig. 1,amispresaedagainstthe pin 36 bymeans of 40 a spring II. The other end ofthe spring bears splint or is secured to a contact member ll lined inbone 88, to which may be connected an electric conductor, which may passwithin the tubular frame II. This structure is shown in detall in Hg. 3,the larger scale of which makes possible the clearer illustration.

'lhe mention of the above described device is as follow:

Rohflon of the wheel of course causes rotaflan of member II and armaturecoils 2| rotate therewith and at the same speed. Ring 24 also rotatuwith the hub and causes rollers 26, which cause the ring internally, torotate in the same direction. Rotation of rollers 26 cause rotation 56of shaft 30, which they engage externally, to take place in the oppositedirection from that of the member I0. The speed ratio between member Illand shaft 30 is equal to the ratioof the internal diameter of ring '24to the external diameter of shaft 30. The rollers 26 do not affect thespeed ratio but do serve to reverse the direction of rotation. Rotationof shaft 30 causes magnets 32 to rotate. The field magnets rotate in adirection opposite to that of the armature coils and hence the relativespeed of rotation between the armature and the field is equal to the sumof their absolute speeds of rotation. This gives a relative speed higherthan that which would be obtained if either the armature or the fieldwere stationary.

The relative rotation between the armature and field generates anelectric current in the armature windings in well-known manner and thiscurrent is led therefrom through theleads 33 and 34. Lead. 33 beinggrounded this side of the circuit is completed through theframe of. the

I bicycle, while the other side is completed through contact pin 36,brush 31, spring 46 and contact member 4|.

If the relative speed of the armature and field is not sufiiciently highwith the arrangement above described to generate the desired voltage, amuch higher speed may be obtained with the arrangement shown in Fig. 3without materially increasing the dimension of the generator. In thisembodiment similar reference characters designate parts similar to thoseshown in Fig. l. Rigidly mounted on the inner end of the lefthand stubshaft I6 is a spider or plate 50. Pins 5| are secured to plate 50 andserve to space and support parallel discs 52. Wheels or rollers 53 aremounted on shafts 54 extending between discs 52. A ring 55 is internallyengaged by rollers 53. Ring 55 is preferably formed with a groovesimilar to groove 25 shown in Fig. 1 and, if desired, may be made ofresilient material so as to better engage the rollers 53. A shaft 56extends through the openings formed in the center of discs 52 and isexternally engaged by rollers 53. These rollers, as well as serving todrive shaft 56, act also as roller bearings for supporting the shaft.Preferably, one or more of the rollers .53 may be mounted on a floatingshaft so that the elasticity of ring 55 may serve to press the rolleragainst shaft 56. Consequently, one or more of the shafts 54 is receivedin holes in plates 52, which holes are of larger diameter than that ofthe shaft so as to permit radial displacement of the latter. Thefloating shaft is provided with heads 32 larger than holes 80 so as toprevent axial displacement of the shaft. A cylindrical casing 51 isrigidly secured to shaft 56. Armature windings 2| are fixed withinmember 51. A ring 6|] is mounted within the open end of member 5'! andis provided with an internal groove. A spider or plate 6| is rigidlysecured to the inner end of the right-hand stub shaft i6 and supportsshafts 62 upon which are rotatably mounted a plurality of rollers 63.Rollers 63 engage ring 60 internally and serve as a roller bearingsupport therefor. The armature assembly, including shaft 56, member 51,ring 60 and coils 2|, is hence rotatably suppormd at one end by rollers53 and at the other end by rollers 63. Rollers 63 also engage a shaft 84externally. Shaft 64 corresponds to shaft 30, shown in Figs. 1 and 2,and is supported at one end by the rollers and at the other by havingits pointed end received in conical recess 23 in shaft 56. Thrustoutward between spokes 2.

nected together in series.

block 3| prevents axial movement of shaft 64. Field elements 32 aremounted on shaft 64. If desired, a cylindrical casing 65 may besupported by plate 6| to form a closure for the rotating parts of thegenerator. v

Current is led from the armature windings 2| in the same manner as thatdisclosed in connection with the first embodiment.

In order that the generator may be disconnected when no current isrequired, ring 55 is not permanently secured to cylindrical member I0.To effect such a connection, a catch member 10 is pivoted at 1| within aslot formed in member ID. One end of member 10 is provided with a detent12 which may engage one of a series of recesses formed in the outer faceof ring 55 so as to lock the ring with member Ill for rotationtherewith. The other end of member 10 is provided with an arm 13 whichextends radially In order that member-10 may be readily manipulated, arod or the like 14 is rotatably secured to arm I3 and extends axiallyoutside of the spokes. A retaining member 15 is secured to the hub andformed with an aperture through which rod 14 extends. A bayo'net slot 16communicates with the aperture and a pin 11 is secured to rod 14. With1e rod in the position shown in Fig. 3 pin 11 en;- gages .the left sideof member 15, as viewed in the figure, and detent 12 is held inengagement with ring 55. In order to release the detent, rod 14 isrotated until pin is in alignment with slot 16, whereupon the rodismoved axially, the pin passing through the slot. This causes member 10to pivot slightly in a clockwise direction, thus moving detent 12 out ofengagement with ring 55. Rod 14 is then rotated to bring pin 17 out ofalignment with slot 16 and the rod is consequently held in thisposition.

The operation of this embodiment is as fol-' lows:

With rod 14 in the position shown in Fig. 3, the detent 12 on member 10engages ring 55 and consequently causes the ring to rotate with themember II). This rotation causes rollers 53 to rotate in the samedirection and to rotate shaft 56 in the opposite direction and at ahigher speed than the speed of the hub. Rotation of shaft 56 causessimilar rotation of member 51, to which are secured armature coils 2|and ring 66.

rotate in the same direction, which causes rotation of shaft 64 in adirection opposite to that of member 5'! and at a still higher speed.Consequently field elements 32 are caused to rotate in a directionopposite to that of armature coils 2|. Inasmuch as armature coils 2|rotate at a higher speed than that of the hub, the relative speed ofrotation between the armature and the field is high. Hence, a highvoltage is generated although the field and armature elements arecomparatively small.

It will be seen that the gearing employed in this embodiment is made upof. two stages con- The first stage comprises the ring 55, rollers 53and shafts 56, while the second stage comprises the ring 60, rollers 63and shaft 64. The field elements are mounted to rotate with the laststep of the last stage, while the armature elements rotate with the laststep ofthe next-to-the-last stage. When there are only two stages,obviously the next-to-the-last stage is also the first stage. However,if still higher relative speeds are desired more than two stages ofgearing may be employed.

The r rotation of ring 60 in turn causes rollers 63 to Instead ofemploying friction rollers, toothed gearingmightbeused.Bowevenirictionairolh ersarecheapenquieterinoperationandservebetterasrollcrbearingsior thecentralshafts which they support, thanwould toothed gearing.

In the appended claims, however, the term "gearings is used in itsbroadest sense and is intended to cover all types of rotary motiontransmitting mechanism.

An advantage oi the embodiment shown in Fig. 3 resides in the fact thatthe electric generator and the gearing constitute a separate unit whichmay be assembled and tested before being placed within the hub. Hence,they also may be removed as aunit ior purposes oi repair.

The embodiments shown in Figs. 1 and 2 may, ii desired, be provided withdisengaging mechanism similar to that shown in Fig. 3, but has beenomitted from the drawing for the sake of simplicity. Likewise, whilepermanent magnets have been shown as field elements, obviously ordinaryfield coils could be employed in constunction with the usual slip ringsfor transmitting current thereto. Also, a well-known commutator could beemployed if a direct current output were desired.

While we have shown two more or less specific embodiments of ourinvention, this has been done for purposes of illustration only and thescope oi our invention is not to be limited thereby, but only by theappended claims viewed in the light of the prior art.

What we claim is:

1. An electric generator including a first rotatable member, a secondrotatable member mounted within and concentric with said first member, aplurality oi. rotatably mounted wheels internally engaging said firstmember and externally engaging said second member for transmittingrotary motion between said members, said first member being resilient soas to irictionally engage said wheel, at least one oi said wheels beingmounted on a floating shaft to permit radial displacement of the wheel,an armature element mounted on one of said members, and a field elementmounted on the other of said members in operative relation with saidarmature element.

2. An electric generator including a first rotatable member, a secondrotatable member mounted within said first member, a pair of parallelfixed annular plates disposed radially between said members, a pluralityof shafts extending between said plates, rotatable wheels supported bysaid shafts, said wheels internally engaging said first member andexternally engaging said second member for transmitting rotary motionbetween said members, an armature element mounted on one of saidmembers, and a field element mountedon the other oi said members inoperative relation to said armature element.

3. An electric generator including a first rotatable member having aninner surface formed with an annular groove the opposite sides of saidgroove forming edges with said inner surface, a second rotatable membermounted within said first member, a rotatably mounted wheel having acontact surface curved in axial direction internally engaging said firstmember at the edges of said groove and externally engaging said secondmember for transmitting rotary motion between said members, an armatureelement mounted on one of said members, and a field element mounted onthe other of said members in operative relation with said armatureelement.

4.Inadevioeoitheclamdescribed,ahollowmemberiormingawheelhunanclectriogenorator within said hub includingarmature and field elements mounted to rotate with respect to each otherand with respect tosaid hub, and means ior driving said elements at aspeed higher than that of said hub.

5. In a device oi the class described, a hollow member iorming a wheelhub, an electric generator within said hub including armature and fieldelements mounted to rotate with respect to each other and with respectto said hub, means for driving one of said elements at a speed higherthan that of said hub, and means for driving the other of said elementsin a reverse direction from that of said one of said elements.

8. In a device oi the class described, a hollow member forming a wheelhub, an electric generator within said hub including armature and fieldelements mounted to rotate with respect to each other and with respectto said hub, means for driving one oi said elements at a speedhigherthanthat 0! said hub, and means for driving the other of said elements in areverse direction from, and at a higher speed than, that of said one ofsaid elements.

'7. In a device of the class described, a hollow member forming a wheelhub, a plurality of stages of rotary motion transmitting mechanismwithin said hub connected in series and driven by said hub, each of saidstages including a gear train, and an electric generator includingrotatably mounted armature and field elements, one oi said elementsbeing connected for rotation with the last gear of the train included inthe ill stage and the other of said elements being connected iorrotation with the last gear of the train included in next to the laststage.

- 8. In a device of the class described, a hollow member forming a wheelhub, a plurality of stages of rotary motion transmitting mechanismwithin said hub connected in series and driven by said hub, each of saidstages including an internal gear driving a shaft through an idlerwheel, and an electric generator including rotatably mounted armatureand field elements, one of said elements being connected for rotationwith the shaft included in the last stage, and the other of saidelements being connected for rotation with the shait included in thenext to the last stage.

9. In a device of the class described, a hollow member forming a wheelhub, a plurality of stages of rotary motion transmitting mechanismwithin said hub connected in series and driven by said hub, each of saidstages including a gear train, and an electric generator includingrotatably mounted armature and field elements, one of said elementsbeing connected for rotation with the last gear of the train included inthe last stage and the other of said elements being connected forrotation with the last gear of the train included in next to the laststage, said last gears being connected for rotation in oppositedirections.

10. In a device oi the class described, a hollow member forming a wheelhub, a plurality of stages oi. rotary motion transmitting mechanismwithin said hub connected in series and driven by said hubQeach of saidstages including an internal gear driving a shaft through an idlerwheel, and an electric generator including rotatably mounted armatureand field elements, one of said elements being connected for rotationwith the shaft included in the last stage, and the other of saidelements being connected for rotation with the shaft included in thenext to the last stage, said shafts being connected for rotation inopposite directions.

11. In a device of the class described, a hollow member forming a wheelhub, a plurality of stages of rotary motion transmitting mechanismwithin said hub and connected in series, each of said stages including agear train, an electric generator including rotatably mounted armatureand field elements, one of said elements being connected for rotationwith the last gear of the train included in the last stage and theother, of said elements being connected for rotation with the last gearof the train included in next to the last stage, and means forselectively coupling the first gear of the first train to said hub forrotation therewith.

12. In a device of the class described, a hollow member forming a wheelhub, spokes secured to said hub, a plurality of stages of rotary motiontransmitting mechanism within said hub and connected in series, each ofsaid stages including a. gear train, an electric generator includingrotatably mounted armature and field elements, one of said elementsbeing connected for rotation with the last gear of the train included inthe last stage and the other of said elements being connected forrotation with the last gear of the train included in next to the laststage, and means including a manipulating member extending said elementsbeing connected for rotation with a gear of said train which rotates ina direction opposite from said last gear, and means for selectivelycoupling said gear train to said hub.

14. In a device of the class described, a hollow member forming a wheelhub, a first rotatable member, means for coupling said first member tosaid hub for rotation therewith, a second rotatablemember arranged insaid hub, a plurality of wheels engaging said first member and saidsecond member for transmitting rotary motion between said members, athird rotatable member arranged in the interior of said second member, aplurality of wheels engaging said second member and said third memberfor transmitting rotary motion from said second member to said thirdmember, an armature mounted on one of said rotatable members and a fieldelement mounted on another of said rotatable members.

S'IEN GUNNAR DALE'N. EMIL EINAR WILHELM ANDERSON.

